Moviegoers went with Just Go With It, which became the top film of the weekend -- but only just. According to studio estimates, the Adam Sandler/Jennifer Aniston rom-com, with $31 million in ticket sales, barely beat out the Justin Bieber concert documentary Never Say Never, which brought in about $30.3 million. Last year Sandler's Grown Ups opened with $40.51 million -- on its way to a final domestic gross of $162 million. However, Just Go With It is expected to see a significant boost in revenue on Monday, Valentine's Day. Meanwhile, appearing in nearly 500 fewer theaters than the Sandler movie, Justin Bieber certainly demonstrated why he is now the reigning teenage idol. His ability to pack movie theaters is clearly as deft as his ability to pack Madison Square Garden and other arenas. (The fewer venues were more than offset by 3D surcharges; Never averaged $9,700 per theater, Go With It , $8,700.) Never took in about the same amount of cash as Miley Cyrus 's similar concert feature film in 2008. But the big surprise of the weekend was the solid performance of the animated Gnomeo & Juliet from Disney's Touchstone Films. While many box-office forecasters predicted on Friday that the film would earn between $15 million and $20 million, it actually wound up with $25 million. The gurus did get it right, however, with The Eagle , which not only didn't fly, but barely got off the ground as it debuted with about $8 million. Overall, the box office grossed $149 million about 27 percent below its year-ago tally for the comparable weekend. It has been lagging 2010 by about 25 percent from the beginning of the year.